Security Installer

HomeSoftwareArchiveTop TipsGlossaryOther Stuff






With so many new and unfamiliar names adorning the sides of CCTV cameras these days (in some instances no names at all…) the Baxall logo is a reassuringly familiar sight. In fact if CCTV cameras were cars Baxall's products would lie somewhere between Volvo and Jaguar in terms of brand awareness perceived reliability and performance.


Baxall cameras are almost instantly recognisable and no matter what the spec might be virtually all recent and current models are housed in a distinctive cream coloured case with a lightly sculptured front and gently curved edges. This uniformity continues on to the recently launched X-Series. We've been taking a close look at the CDX9714, one of two models in the range, the principle difference being the type of power supply. The 9714 is mains powered (98-260VAC) whilst its stablemate, the CDX9714L/V requires an 11-40 VDC or 12-30VAC supply.


The key features are above average low-light sensitivity and resolution plus extensive use of digital signal processing (DSP), which together means the camera can function in a wide range of conditions including difficult situations where most regular general purpose models would not be able to cope.


As usual we'll begin the tour with the image sensor and this particular modes uses a 1/2-inch Sony Exview HAD device with a claimed minimum sensitivity of 0.4 lux (f1.2). Resolution is towards the high end of the performance range at 480 lines. Exposure options include an electronic iris, switchable AGC, configurable backlight compensation, adjustable gamma correction, 4-mode white balance, auto/manual shutter and connections for an auto-iris lens. There are some interesting extras too, such as Peak White Inversion (PWI) -- more about that in a moment -- and 'flickerless' operation, when the camera is used in some types of tube lighting.


The 9714 has a standard C/CS mounting thread at the front of the case with back focus adjustment handled by a pair of screws on the top and side of the case. This is very convenient if, for example, access to one of the screws is hindered by a wall or ceiling. On the right side of the unit there's standard square four-pin socket for an auto iris lens and a hinged flap that opens to reveal three banks of miniature DIP switches, a push button switch for displaying the backlight compensation 'window' and two rotary presets for auto-iris lens level and PWI threshold.


DIP switch 1 (SW1) covers AGC (on/off), line-lock phase (fixed/adjustable), sync (internal/line-lock) and the position and shape of the backlight compensation window. Three DIP switches provide 8 permutations or patterns – shown by an opaque window,  temporarily superimposed on the image -- covering the central area, top and sides of the picture.


DIP switch 2 (SW2) is used to set manual shutter speeds and flickerless mode; the four switches provide 8 speed settings, from 1/50th sec to 1/10,000th sec. The first two positions on SW3 are used to set colour balance mode (auto, fluorescent, indoor & outdoor), position 3 is for gamma correction (normal 0.45/linear 1.0) and the fourth switch enables Peak White Inversion. Briefly, when PWI is switched on very bright areas of the image are displayed as black. This can be used to help overcomes exposure problems when using some types of auto-iris lens, which can react to excessive scene brightness by closing down resulting in a loss of detail in darker parts of the image.


The backside of the camera is recessed by around a centimetre. This is very neat touch as it stops the sockets and connectors protruding, reducing the overall length of the camera when it is installed and at the same time providing some protection for the connections. Two panel mounted BNC sockets carry the composite video output and an input for external synch (genlock). A separate Y/C (S-Video) socket is also provided in the shape of a standard 4-pin mini DIN connector. A two-way spring terminal carries the connections for a voltage controlled type auto iris lens and there's a recessed preset for adjusting line-level phase (when the camera is powered fro an AC source). A green LED indicator shows power on and the captive main lead emerges from a collett close to the bottom right hand corner of the back panel.


The top and bottom halves of the case are lightweight but very tough alloy extrusions; the end caps are plastic mouldings. It's quite busy inside the case with the shielded mains supply module taking up around a third of the available space. The absence of a bulky transformer and the wide mains voltage operating range suggests it is an efficient switched mode type supply and appears to be confirmed by the fact that there are no hot spots and the camera body never becomes more that slightly warm to the touch.


There are five other circuit boards inside the case, attached to a steel sub-frame. The two on the right side are involved with video processing and the various DSP functions, one at the front – mounted on the back focus adjustment mechanism supports the CCD image sensor. A board in the base of the camera acts like a motherboard providing connection to the other PCBs and finally there's one in the back of the case, which handles the rear panel connections. Overall it appears to be very well constructed with a minimum of wiring, in fact the only visible connections are the three mains wires and a ribbon cable from the image sensor board to the video processor PCB. It's very stable too and the image never missed a beat when subjected to a healthy dose of the Bench Test intermittency test, courtesy of the workshop rubber mallet.



In most cases installation should prove relatively painless, mechanically there are no problems and standard 1/4-inch threaded mounting bosses are built into the top and bottom panels on the case. The back focus adjustment is quite smooth; unusually there's no provision for locking the mechanism but this doesn't appear to be a problem and the setting remains stable and unaffected by physical shock or vibration.


The only potential trouble spot is likely to be the miniature DIP switches. They are very small indeed, verging on the microscopic, and quite deeply recessed so that adjusting them in-situ could pose problems when the side of the camera is mounted close to a wall. All of the setup operations are reasonably straightforward and outlined in a fair amount of detail in the instructions. The booklet is generally well presented though for some reason it makes no mention of the back panel layout nor will novice installers find much in the way of explanation for the function and operation of features like gamma correction or the electronic shutter.



Resolution on our sample is within a whisker of the manufacturer's specs and in good light the image is packed with fine detail so it would be well suited to systems using high performance monitors and recording equipment. Low light performance is good but largely dependent on the AGC being enabled, which then has an impact on scene brightness and noise levels at higher lighting levels. There doesn't seem to be a happy medium and some experimentation may be necessary to get a well-balanced image when there is a wide variation in scene brightness. Image quality in good light is fine, there's plenty of sharp detail. Very little noise and colours are crisply defined and natural looking. The auto colour balance system responds well to change in lighting type though scenes lit exclusively by tube lighting can have a slightly yellowish tinge, even when the white balance system is set to fluorescent. The auto iris system is fairly agile and reacts quickly to sudden changes in scene illumination; the Peak White Inversion feature looks as though it could have applications over and above the ones suggested and it could prove useful in locations with areas of high level lighting, that the backlight compensation facility cannot cope with.



The CDX9714 slots in neatly between costly high-performance specialist cameras and the vast majority of mid-range and general purpose cameras. It's a solid, workmanlike design with enough manual adjustments to ensure a useable image in al but the most unfavourable conditions. It's reasonably easy to set up and devoid of any superfluous gadgetry or the kind of expensive bells and whistles that would rule it out as uneconomical for marginally difficult installations. Build quality is good and there's every reason to suppose it will not harm Baxall's well earned reputation for reliability and longevity. In short a very decent camera, a useful addition to any system that's capable of making use of its low light abilities facility to resolve fine detail and definitely worth considering for moderately tricky jobs. 



Design and design features                      ****

Circuitry and components                ****

Ease of installation and wiring            ****

Range and variety of functions            ****

Accompanying instructions              *****                        

Technical advice and backup            ****    

Value for money                         ??                          



ă R. Maybury 2001 1510



[Home][Software][Archive][Top Tips][Glossary][Other Stuff]

Copyright (c) 2005 Rick Maybury Ltd.